Ductal carcinoma in situ in a 25-year-old man presenting with apparent unilateral gynecomastia

Ductal carcinoma in situ (DCIS) in a young man is rarely reported. Our patient, a 25-year-old man, presented with apparent symptomatic unilateral gynecomastia. He has a strong history of cancer on both the maternal and paternal sides of his family, including breast and lung (maternal) and melanoma, colon, and pancreatic (paternal). His mother tested negative for BRCA1 and BRCA2. There is no information on paternal genetic testing.The patient …